مدل سازی اجزا محدود پانل های آجرکار تقویت شده با رویه بتن الیافی تحت بارگذاری درون صفحه

نوع مقاله: علمی - پژوهشی

نویسندگان

1 استادیار، دانشکده مهندسی عمران و محیط زیست، دانشگاه صنعتی شیراز، شیراز، ایران

2 دانشجوی کارشناسی ارشد گرایش زلزله، دانشکده مهندسی عمران و محیط زیست، دانشگاه صنعتی شیراز، شیراز، ایران

چکیده

امروزه تحقیقات گسترده ای بر روی رفتار لرزه ای دیوارهای مصالح بنایی غیرمسلح و روش های متنوع مقاوم سازی آنها توسط محققین مختلف در حال انجام است. اکثر روش های پیشنهادی برای تقویت دیوارهای مصالح بنایی استفاده از یک رویه خارجی می باشد. اخیرا استفاده از رویه بتنی الیافی به عنوان روشی برای تقویت دیوارهای مصالح بنایی موجود در قالب تحقیقات عمدتا آزمایشگاهی ارزیابی شده است. از این رو در این تحقیق یک مدل اجزا محدود میکرو برای دیوارهای مصالح بنایی تقویت شده توسط رویه بتن الیافی تحت تلاش های درون صفحه در نرم افزار اجزا محدود ABAQUS ارائه شده است. برای مدل سازی آجر و ملات نیز از مدل آسیب خمیری بتن استفاده شده است. بدین ترتیب ابتدا مدل عددی پیشنهاد شده برای دیوارهای مصالح بنایی تحت نیروهای درون صفحه شرح داده شده و روش مذکور با استفاده از مدل سازی پانل های مصالح بنایی تقویت شده با رویه بتنی الیافی مسلح شده با الیاف فولادی که قبلا در قالب یک تحقیق آزمایشگاهی ارزیابی شده اند، راست آزمایی شده است. مقایسه نتایج حاصل از تحلیل های انجام شده با نتایج حاصل از آزمایش ها نشان از دقت قابل قبول روش مدل سازی پیشنهادی دارد. در ادامه با استفاده از روش مدل سازی پیشنهادی، اثر برخی پارامترها از جمله ضخامت رویه، میزان الیاف در بتن الیافی و وجه تقویت شده پانل بر مقاومت و رفتار درون صفحه پانل های تقویت شده مورد ارزیابی قرار گرفته است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Finite Element Modeling of Brickwork Panels Strengthened with Fiber Reinforced Concrete layer

نویسندگان [English]

  • Mohammad Amir Najafgholipour 1
  • Seyed Mehdi Dehghan 1
  • Ali Reza Kamrava 2
1 Assistant Professor, Department of Civil and Environmental Engineering, Shiraz University of Technology, Shiraz, Iran
2 M.Sc. Student, Department of Civil and Environmental Engineering, Shiraz University of Technology. Shiraz, Iran
چکیده [English]

Several researches have been carried out on seismic behavior and retrofitting of unreinforced masonry (URM) walls. Using an external retrofitting surface layer is the most popular strengthening technique for URM walls. Recently, using fiber reinforced concrete (FRC) overlay as a strengthening technique for URM walls is evaluated though a series of experimental studies. Therefore, in this paper finite element modeling of URM walls strengthened with FRC layer under in-plane actions is considered through a micro modeling approach in finite element software ABAQUS. Concrete Damage Plasticity Model is used for modeling of brick unites and mortar joints. In this article the finite element modeling of the retrofitted walls is explained and is verified with results of a previous experimental study. Results obtained from analyzes show that the finite element model can simulate the in-plane behavior of strengthened URM walls well. In addition, a parametric study is performed and the influence of some parameters such as FRC surface layer thickness, fiber content and retrofitted face of the panel on the in-plane capacity of the strengthened masonry panels is evaluated. Analysis results show that the FRC overlay thickness and retrofitted face of the wall has considerable effects on the in-plane strength of retrofitted URM walls.

کلیدواژه‌ها [English]

  • Unreinforced masonry wall
  • In-plane shear
  • Seismic Retrofitting
  • Fiber reinforced concrete
  • Finite element model

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